I’m extremely skeptical that an 8 year old would be suicidal because of bullying, let alone murder-suicide.
You should be skeptical. My best guess is Mom was using the media’s relentless “public service announcements” about bullying as a VERY convenient excuse for her homicidal tendencies.
If I’m wrong ... Oh well ...
I am skeptical that he would be physically or emotionally or technically able to hang his sister, and then be able to hang himself after seeing her terror and suffering.